Hi,

Question regarding pressures in a Ruger No1 375 H&H.

As this is my first No1, I'm uncertain what I should be looking for, I have plenty of experience with various bolt action rifles and can feel the difference when bolt lift becomes harder.

What happens with the Ruger No1 is with new brass and once fired brass.

I'm using starting loads from reputable books, cases are Remington, powder is hand weighed, no velocity differences are seen at the chrony.
This happens with jacketed and cast projectiles.
Typical load, 300gn Hornady SPBT, 73gn of 2209 (H4350), Fed 210M, R&P Brass, vel 2365fps.

Out of say 50 rounds I get several cases that cause a hesitation at the primary extraction point in the levers cycle while others simply fall from the chamber.
Once these tight cases are FLS they rechamber and extract easily.

When I reinsert the tight case and close then open the action I get the same slightly tight extraction.

As I go up in powder charges the problem gets worse, though many cases still fall from the chamber easily.

FLS the brass fixes the problem but causes cases to grow by 8-10thou each time I FLS.

Any thoughts?

Thanks

Perhaps you have a slightly oval, imperfect chamber, and the normal pressure variations produce the occasional eccentric case that drags on extraction?

Or perhaps just a slightly rough chamber that could be improved by polishing a bit?

Any visible marks (rings) on the brass?
Any detectable/measurable/visible bulges or asymmetry of the fired case?

Normal max pressures to 62K psi should be fine in the Ruger No.1.
That tapered .375 H&H case should extract easily with good chamber and good brass.


My first bolt action rifle was a Ruger M77 30-06, in 1978.
It had an asymmetric chamber that produced out-of-round cases just forward of the web.
Still does, and still shoots 0.5 MOA with handloads.
In fact it is now my "tactical deer rifle" in a Brown Precision stock with Springfield Armory ballistic reticle 4X-12X scope.

... From my cold, dead hands,
... or when I go blind,
... but I will keep the shotguns if just blind.

Hi x-rings,

In my 338 win mag and 375 H&H #1s, while working up loads, I have had some pretty hot loads. I never experienced anything like what you are describing. Rip my be correct, the chamber may have a problem. A chamber cast would show any problems.

I hate to ask a stupid question, but.... is the chamber clean?

Hi,

I measured my cases and can't find any eccentricity.
The web just in front of the belt measures .513 on the tight cases.

A fellow ruger No1 shooter told me the problem may be softer brass in some case, however this doesn't fit as I'm using Norma and Rem cases and getting the same problem with both.
Plus loads are at or below starting loading data, so pressures should be low.

I've also noted some cases have a drag mark
across the base from primer to circumference of the rim, but not all cases show this.

Anyway thanks for the advice

I have a Ruger #1 in 500 nitro and have hot loads for it and never had a problem . I have run loads to 2375 ft/sec with 570 grain bullets = 7140 ft.lbs of energy and they extract fine. I would be looking at a possible brass problem too.

Most likely you have a chamber that is a little rough - meaning it still has rings in it from the reamer. The .375 H&H has a good bit of taper and cases should fall out of the chamber with any sane load.

quote:

I've also noted some cases have a drag mark across the base from primer to circumference of the rim, but not all cases show this.

That is an important clue. If the firing pin does not retract fully it can hand up in the primer and drag on the case head, causing hard extraction. This makes more sense than an out-of-round or banana-shaped chamber....although I have had both things happen. Your very low-pressure loads should not cause tight extraction in a defective chamber if you can't see the defect. Take out the breach block and check for a bad firing pin retraction spring or junk in the assembly.



.

quote:

Originally posted by TX Nimrod:

quote:

I've also noted some cases have a drag mark across the base from primer to circumference of the rim, but not all cases show this.

That is an important clue. If the firing pin does not retract fully it can hand up in the primer and drag on the case head, causing hard extraction. This makes more sense than an out-of-round or banana-shaped chamber....although I have had both things happen. Your very low-pressure loads should not cause tight extraction in a defective chamber if you can't see the defect. Take out the breach block and check for a bad firing pin retraction spring or junk in the assembly.



.

Very good point.
Could just be some congealed lubricant.
Might be fixed by degreasing the firing pin assembly and relubricating with BreakFree CLP.

For a hunter's use, I am not certain that the firing pin (striker shaft) or its spring should be oiled at all.

There is no significnt friction on a No.1 firing pin, and oil is a natural for holding dirt, grit, etc. Likewise many oils or greases congeal to some extent at temperatures above the freezing point of water.

When I was hunting the far north in Canada...,or any part of Canada in the fall, winter, or spring, for 17 years I kept the firing pin and its spring almost surgically clean of oils and greases. Never had any misfires or broken parts from that practice, and my chrono didn't show it to create any erratic ignition..

I've never oiled the pin in my 375 No. 1 - in below 0 Fahrenheit I have had a couple of bolt guns freeze up, but not my No. 1. It was about 20below in the pic in my avatar.

I've also loaded some pretty hot loads in it (slightly above book) and never had extraction issues.

I always lightly lubricate firing pin with CLP.
I hunted 5 years in Alaska like that.
On one November caribou hunt I did degrease and
dust the firing pin with graphite.
Using no lubricant for a week in subzero is OK too,
but then it would get cleaned and lubricated with CLP
as soon as I got back to warmth and humidity.

Congealed grease locked up my Merkel 470NE.
One firing pin did not rebound and stayed in the primer indent.
That break action would not break open.
Degreasing and relubrication was the fix.
Should be done regularly for reliability,
And that includes all the internal lock mechanism too.

I also have a Ruger Red Label 20 guage
that Butch Searcy added .338WinMag barrels set to for DR O/U.
Eventually a booger on one of the Ruger firing pins reared its head.
Removing the firing pin and polishing the metal burr off of it
cured that occasional hard extraction/lockup of the action.